1. Field of the Invention
The present invention relates to a pressure boosting showerhead, and more particularly to a pressure boosting showerhead for preventing water flow reversely penetrating into the air circulation path and boosting pressure to maintain the water outflow of the showerhead with better impact strength to thereby achieve the purpose of saving water.
2. Brief Description of the Related Art
For the purpose of saving water, a conventional showerhead usually uses the structure of mixing air into water outflow to increase the impact strength of water outflow, such as U.S. Pat. No. 5,111,994 (the structure is shown in FIG. 1), U.S. Pat. No. 7,611.070 (the structure is shown in FIG. 2). The prior arts all have a common point that leading into outside air via air inlets 11, 21, sending out air via air outlets 12, 22 to mix with water outflow and boost pressure for spraying. Basically, these kinds of method are all used to increase the impact strength of water outflow, namely, using less water to let the user feel the effect of water outflow impacting. However, the abovementioned structure has a defect in using. Outside air gets into the showerhead due to leading of water outflow. But air outlets 12, 22 are not designed as watertight. Part of the strong water flow may reversely infiltrate into air outlets 12, 22 and may obstruct outlet and interference the mixing air amount, pressure of the mixing water flow may be reduced and the impact strength of water outflow may become weaker. So the user may feel that the water outflow amount is not enough, and increase the water outflow amount to look for water outflow with larger impact strength. Thus, the amount of using water is increased and the purpose of saving water can not be achieved.